Configuring IOA

In this chapter, all configuration steps relate to a reference topology shown in Figure 4-1 where SJC and RTP represent two sites connected through the WAN or MAN ISLs. In this example, sjc-sw2 and rtp-sw2 represent the core switches where IOA is deployed. sjc-sw1 and rtp-sw1 are edge switches that has the hosts or targets connected to them.

Figure 4-1 IOA CLI Reference Topology

The process of configuring IOA involves a number of configuration tasks that should be completed in order:

Enabling Clustering

The first step in the process of configuring IOA is to enable clustering in all of the IOA switches.

To enable or disable the IOA cluster on sjc-sw2, perform this task:

Command

Purpose

Step 1

sjc-sw2# conf t

sjc-sw2(config)#

Enters configuration mode.

Step 2

sjc-sw2(config)# feature cluster

Enables clustering.

sjc-sw2(config)# no feature cluster

Disables clustering.

To complete the configuration for the reference topology, enable clustering in rtp-sw2.

Enabling the IOA Service

After enabling the IOA cluster, the second step in the process of configuring IOA is to enable the IOA service on each of the IOA switches.

To enable the IOA service on sjc-sw2, perform this task:

Command

Purpose

Step 1

sjc-sw2# config t

Enters configuration mode.

Step 2

sjc-sw2(config)# feature ioa

Enables IOA feature.

sjc-sw2(config)# nofeature ioa

Disables IOA feature.

To complete the configuration for the reference topology, enable the IOA service in rtp-sw2.

Classifying the Switches to IOA Sites

Each of the IOA switches need to be classified into a site. Make sure that you classify only the IOA switches within the physical site into an IOA site.

To classify an IOA switch into the SJC site, perform this task:

Command

Purpose

Step 1

sjc-sw2# config t

sjc-sw2(config)#

Enters configuration mode.

Step 2

sjc-sw2(config)# ioa site-local SJC

Configures the site to which the switch belongs to. The maximum name length is restricted to 31 alphabetical characters.

Note This command configures the site to which the switch belongs to across all the IOA clusters that the switch participates in.

To complete the configuration for the reference topology, classify rtp-sw2 into RTP site.

Configuring IOA Interfaces

After enabling the cluster and enabling IOA, configure the IOA interfaces on the switch.

To provision an IOA interface, perform this task:

Command

Purpose

Step 1

sjc-sw2# config t

sjc-sw2(config)#

Enters configuration mode.

Step 2

sjc-sw2(config)# interface ioa 2/1

Configures IOA on service engine 1 in slot 2.

sjc-sw2(config)# interface ioa 2/2

Configures IOA on service engine 2 in slot 2.

Note Service engines 2, 3, and 4 are available only on the SSN-16 module. The appropriate IOA license is checked out as a part of the creation of the interface.

A standard MDS notation is used to denote the IOA interfaces: ioaslot/service engine. For example, ioa2/1 refers to Slot 1, Service Engine 1. In the case of the MSM-18/4 Module and 9222i Switch, only one service engine exists and so only ioa2/1 is valid. In the case of the SSN-16 Module, four service engines exist and so ioa2/1, ioa2/2, ioa2/3, and ioa2/4 are valid interfaces.

sjc-sw2(config)# no interface ioa 2/2

Deletes the IOA interface.

Note Before deleting an IOA interface, you must remove the IOA interface from the cluster.

Step 3

sjc-sw2(config-if)# no shutdown

Enables the IOA interface.

sjc-sw2(config-if)# shutdown

Disables the IOA interface.

Note FCIP and IOA are not supported on the same engine.

To complete the configuration for the reference topology, configure the interfaces in rtp-sw2.

Displaying IOA Interface Status

After configuring the IOA interface, use the show int command to show whether the IOA interface is down. The interface is down until the interface is added to a cluster:

sjc-sw2# show interface ioa 2/1

ioa2/1 is down (Not in any Cluster)

0 device packets in, 0 device packets out

0 device bytes in, 0 device bytes out

0 peer packets in, 0 peer packets out

0 peer bytes in, 0 peer bytes out

0 i-t create request, 0 i-t create destroy

0 i-t activate request, 0 i-t deactivate request

Possible reasons for the interface being down are as follows:

•Administratively down—The interface is shut down.

•Not in any cluster—The interface is not part of any IOA cluster.

•Port software failure—A software failure has occured causing a reset of the IOA service engine.

•No license—The interface does not have a valid IOA license. The license is either not installed or all the available licenses are in use.

Configuring an IOA Cluster

To configure a cluster, start with a switch and create a cluster and add the remaining IOA switches into the cluster. From this point on, all cluster parameters can be configured from this switch.

To create an IOA cluster, perform this task:

Command

Purpose

Step 1

sjc-sw2# config t

sjc-sw2(config)#

Enters configuration mode.

Step 2

sjc-sw2(config)# ioa cluster tape_vault

sjc-sw2(config-ioa-cl)#

Assigns a user-specified name (tape_vault) to the IOA cluster. The maximum length of the name is 31 alphabetical characters. Enters the cluster configuration submode. The local switch is implicitly added to the cluster as part of this command.

sjc-sw2(config)# no ioa cluster tape_vault

Deletes the specified IOA cluster.

Note You need to select a switch that you would like it to be the master switch as the seed switch when you create the IOA cluster. If you have multiple switches in a site, you may add all the switches in a site that you would like to manage from to the cluster before adding the switches from the remote site.

IOA Flow Setup Wizard

You can use the IOA Flow Setup Wizard to simplify the provisioning of flows especially when there are many flows to provision, and when you add, remove, or replace host HBAs, tape drives or storage controllers.

Prerequisites for IOA Flow Setup Wizard

The following prerequisites must be met before you can invoke the IOA Flow Setup Wizard:

•All of the N ports of both initiators and targets that need to be accelerated must be online.

•The zoning configuration must already be in place to permit the flows that need to communicate with each other. If you are replacing a host HBA, you must update the zoning configuration to remove the faulty HBA and to add the new HBA before you invoke the IOA Flow Setup Wizard.

Using the IOA Flow Setup Wizard

The wizard processes the active zone set for the VSAN and creates a set of candidate flows. The zone set may have local flows as well as flows that traverse across sites. The IOA Flow Setup Wizard runs through a series of steps as listed in this procedure to prune the list to capture only the flows that traverse across the sites that need to be accelerated.

Step 2 Classify the switches in the candidate switch list into appropriate sites.

This step is only for those switches where none of the hosts or targets have been configured yet for acceleration.From the flows in the active zone set, a candidate switch list is prepared based on where the hosts and targets are logged into.

Do you want to configure the n-port to site mappings? (yes/no) [yes] yes

Step 4 (Optional) This step is presented only when some of the N-ports such as those used in remote replication, are represented as scsi-fcp(both) in the FCNS database. Enter the primary direction of the traffic that will be used by IOA to decide on what should be configured as host and target in IOA.

Replication traffic can flow in either direction.

Certain N-ports in this VSAN can act as both initiator and targets

Is the traffic flow primarily from sjc to rtp? (yes/no) [yes] yes

Step 5 The wizard configures the list of flows that are not already configured in IOA and attempts to delete the IOA flows that are not part of the zone set. This operation specifically handles removing HBAs or storage controllers. Enter yes to accept the flows that need to be accelerated. New flows that need to be accelerated are displayed.

Creating Multiple IOA Clusters on a Single Switch

Figure 4-2 illustrates the IOA implementation where the IOA service is extended across multiple sites. In the illustration, Site-SJC consolidates the tape backup from Site-RTP and Site-SAC. Each IOA cluster represents a site pair, which means there are two unique clusters. This topology provides segregation and scalability of the IOA service across multiple sites. In the Site-SJC, a single switch can participate in multiple IOA clusters.

Figure 4-2 Extended Across Multiple Sites

Note Before creating another cluster on sjc-sw2, create a third site SAC with the sac-sw2 switch. Clustering and IOA service must be enabled, and IOA interfaces must have been provisioned on the sac-sw2 switch.

To create another IOA cluster on sjc-sw2 with SAC, follow these steps:

Command

Purpose

Step 1

sjc-sw2# config t

Enters configuration mode.

Step 2

sjc-sw2(config)# ioa cluster tape_vault_site2

Specifies the cluster name and enters IOA cluster configuration submode. A cluster name can include a maximum of 31 alphabetical characters.

Step 3

sjc-sw2(config-ioa-cl)# node local

Adds the local switch to the cluster. Enters the node configuration mode.

sjc-sw2(config-ioa-cl-node)# interface ioa2/3

Adds the IOA interface to the cluster.

Step 4

sjc-sw2(config-ioa-cl)# node sac-sw2

Adds the remote node to the cluster and enters the node configuration mode.

sjc-sw2(config-ioa-cl-node)# interface ioa2/3

Adds the IOA interface to the cluster.

The following example displays the multiple clusters created using the SJC site:

Note You need to select a switch that you would like it to be the master switch as the seed switch when you create the IOA cluster. If you have multiple switches in a site, you may add all the switches in a site that you would like to manage from to the cluster before adding the switches from the remote site.

Note In this example, the SJC site may be a natural consolidation point for management, and you may choose a switch from this site as the preferred master switch.

Shutting Down a Cluster

Specifies the cluster name and enters IOA cluster configuration submode. A cluster name can include a maximum of 31 alphabetical characters.

Step 3

sjc-sw2(config-ioa-cl)# shut

Shuts down the cluster. This command must be used to recover a cluster when it is partitioned. The change can be disruptive. For more information see "Cluster Recovery Scenarios, page B-5.

Load Balancing the Flows

To load balance the flows, perform this task:

Command

Purpose

Step 1

sjc-sw2# config t

Enters configuration mode.

Step 2

sjc-sw2(config)# ioa cluster tape_vault

Enters the cluster configuration mode.

Step 3

sjc-sw2(config-ioa-cl)# load-balancing

Load balance all the IOA flows. This process is disruptive and causes the hosts to relogin into targets. The load-balancing command will take some time to execute depending on the number of flows. You should not abort the command in the middle of its execution.

sjc-sw2(config-ioa-cl)# load-balancing enable

You may enter the load-balancing enable command only when you abort the load-balancing command process. The load-balancingenable command turns on the load-balancing attribute for the new flows.

sjc-sw2(config-ioa-cl)# load-balancing 11:22:33:44:55:66:77:88

Load balance specified targets in the IOA flows. This process is disruptive and causes the hosts to re-login into targets. The load-balancing command will take some time to execute depending on the number of flows. You should not abort the command in the middle of its execution.

Setting the Tunable Parameters

To set the the following tunable parameters based on your deployment requirements, perform this task:

Command

Purpose

sjc-sw2(config-ioa-cl)# tune round-trip-time ms

Specifies the round-trip time in milliseconds. It is the time taken by the IOA data packet to traverse between two sites. The value can vary from 1 to 100 ms. 15 ms is the default.

sjc-sw2(config-ioa-cl)# tune lrtp-retx-timeout msec

Specifies the LRTP retransmit timeout in milliseconds. It is the time to wait before LRTP starts retransmitting packets. The value can vary from 500 to 5000 msec. 2500 msec is the default.

Caution The following are advanced tunable parameters and you must consult Cisco Services and Support team before tuning these parameters.

To set the the following advanced tunable parameters based on your deployment requirements, perform this task:

Command

Purpose

sjc-sw2# config t

Enters configuration mode.

sjc-sw2(config)# ioa cluster tape_vault

Enters the cluster configuration mode.

sjc-sw2(config-ioa-cl)# tune timer rscn-suppression seconds

Specifies the IOA RSCN suppression timer value. It is the amount of time the IOA process waits before it queries FCNS (name server) after learning about changes in the network. This helps alleviate the amount of duplicate or repeating query in case of rapid network changes. The value can vary from 1 to 10 seconds. 5 seconds is the default.

sjc-sw2(config-ioa-cl)# tune timer load-balance target seconds

Specifies a IOA target loadbalance timer value. It is the amount of time the IOA process waits before it attempts to load balance all IT Nexuses of a certain target port after a change in connectivity has been detected. The value can vary from 2 to 30 seconds. 2 seconds is the default.

sjc-sw2(config-ioa-cl)# tune timer load-balance global seconds

Specifies a global IOA load-balance timer value. It is the amount of time the IOA process waits before it attempts to load balance all IT Nexuses configured in a cluster after a change in connectivity has been detected. The value can vary from 5 to 30 seconds. 5 seconds is the default.

sjc-sw2(config-ioa-cl)# tune ta-buffer-size KB

Specifies the tape acceleration buffer size in KB. It is the amount of buffering allowed for flow control during tape acceleration. The value can vary from 64 to 12288 KB or Auto. Auto is the default. Auto option takes WAN latencies and speed of the tape device into account to provide optimum performance.

sjc-sw2(config-ioa-cl)# tune wa-buffer-size MB

Specifies the write acceleration buffer size in MB. It is the amount of buffering allowed for flow control during write acceleration. The value can vary from 50 to 100 MB. 70 MB is the default.

sjc-sw2(config-ioa-cl)# tune wa-max-table-size KB

Specifies the Write Max Table size in KB. It is the maximum number of active exchanges supported on an IOA flow. The value can vary from 4 to 64 KB. 4 KB is the default.